Ukrainian <- English for Russian speakers

Firstly, let me thank You for all the hours dedicated to this Project for the sake of all the learners of the world!

I want to ask a straightforward question...

Is it a good idea for people who are proficient in Russian to start this course? Or, maybe, it will be a longer path, since, I guess, there is an overlap in Russian and Ukrainian lexicon, grammar, and it's better to go out of Duolingo and find books/tutorials for direct RU -> UKR experience?

I believe, for those who are absolutely fluent in Russian or native Russians, typing phrases with similar words in the course would be a boring thing. You'll learn efficiently, if you start to read and listen to Ukrainian text/videos. There are a lot of news sites with articles in both languages and on YouTube one can find Ukrainian videos with russian subtitles. Happy learning!

I think it depends on how good you are - I know some, but I still think it will be better for me ENG -> UKR. But if you're proficient, I recommend just using flashcards. The grammar is all the same, from what I understand, just a few different works. 70% lexical similarity is between Ukrainian and Russian, I think.